code-review

A code-review process that checks a diff, branch, path, or pull request for correctness, simplification, efficiency, and reuse.

In plain words
What is it for?
Use it to review local changes or a pull request and receive findings ordered by severity.
Why use it?
It includes untracked files and rechecks findings against the actual code, reducing reports based only on common patterns or assumptions.

Skill for Claude CodeCodex

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add skills/mitodl/agent-kit/code-review
Any agent
npx skills add mitodl/agent-kit --skill code-review
Clone the repo
git clone --depth 1 https://github.com/mitodl/agent-kit

Made for: Claude Code, Codex.

Per session 148 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,908 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00148 $0.01908
Opus 5 $0.00074 $0.00954
Sonnet 5 $0.00030 $0.00382
Haiku 4.5 $0.00015 $0.00191

Measured yesterday against content hash 6a4cb10a8ee8, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

code-review scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured yesterday.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

skills/process/code-review/SKILL.md · 166 lines

How it starts

The opening of the file, as written. The whole thing — 166 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Code Review

Reviews a diff against four dimensions — correctness, simplification, efficiency, reuse — and reports findings as a severity-ordered table. Every finding is re-checked against the actual code before it ships, so the report doesn't carry a pattern-matched guess dressed up as a bug.

See references/dimensions.md for the four dimensions with worked examples of a real finding vs. a non-finding. See references/findings-format.md for the table schema and a full worked example.

Scope input

Resolve what to review from the request, in this order:

  1. No target given — combine three sources: git diff (unstaged, tracked changes), git diff --staged, and untracked files. Plain git diff/git diff --staged never show untracked files — a working tree containing only a brand-new file looks empty to both — so check git status --porcelain for ?? entries and include them (git add -N <file> first makes each show up as an addition in the plain git diff without staging its content). Only fall back to git diff HEAD~1 when all three are empty, and say explicitly that's what's being reviewed instead of silently reporting nothing.
  2. A branch name — diff against where it forked from the default branch, not a plain two-dot diff: detect the default branch via git symbolic-ref refs/remotes/origin/HEAD. That ref only exists once a remote's HEAD has been set (git clone usually does this, but a fresh/local-only repo or an unset remote won't have it — verified: a bare git init with no remote raises "not a symbolic ref"); when it's missing, fall back to gh repo view --json defaultBranchRef --jq .defaultBranchRef.name if gh and a GitHub remote are available, otherwise ask the user which branch to diff against rather than guessing main or master. However the default branch was found, find the merge base (git merge-base <default> <branch>), then git diff <merge-base>...<branch>.
  3. A pathgit diff HEAD -- <path> (covers staged and unstaged changes to the path in one call — plain git diff -- <path> shows only unstaged, so a fully-staged change at that path would otherwise look like an empty diff), plus the same untracked-file handling as rule 1, scoped to that path. Same default-branch detection as rule 2 if a branch was also named.
  4. A PR number — when gh is available and the repo has a GitHub remote, gh pr diff <number>.

Read the full file on GitHub · 166 lines

Files

What ships with it

2 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. yesterday First seen · 166 lines · 148 tokens per session scan A 6a4cb10a8ee8

Subscribe to this mod's changes

code-review is a skill published in the GitHub repository mitodl/agent-kit (2 stars, last pushed 3d ago), licensed BSD-3-Clause. It adds 148 tokens to every session and 1,908 once invoked, about $0.0007 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

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